“This is looking like being one of the coldest periods we have had in the UK for a number of years with almost anywhere at risk of seeing snow over the next few days,” the UK Met Office said February 27, 2018. Amber and Yellow National Severe Weather Warnings for snow, snow and wind, and snow and ice have been issued for many regions as bands of snow showers move across the UK.

Bitter easterly winds from northern Scandinavia and northwest Russia are crossing the United Kingdom bringing cold air and significant wind chill risk through the week. However, even without the wind chill some locations will struggle to get above 0 °C (32 °F) during the day, with night-time temperatures down to -8 °C (17.6 °F) quite widely at times. The lowest temperatures of this spell are expected Wednesday, February 28 and Thursday, March 1 meaning the cold winter weather will continue into the start of meteorological spring.

Frequent and heavy snow showers are expected on Wednesday and Thursday leading to some significant accumulations developing. Long delays and cancellations on bus, rail and air travel could occur. Roads may become blocked by deep snow, with many stranded vehicles and passengers. Some rural communities might be cut off for several days. Long interruptions to power supplies and other services such as telephone and mobile phone networks, could occur.

Amber Warning for snow is in effect between 06:00 local time, February 28 and 18:00 local time, March 1 for the following regions:

Central, Tayside & Fife

Grampian

Highlands & Eilean Siar

North East England

North West England

SW Scotland, Lothian Borders

Strathclyde

Yorkshire & Humber

“Snow showers will bring variable snow cover, but parts of northeast England and Scotland are expected to see the most frequent snow showers from Wednesday morning to Thursday afternoon,” Met Office Chief Forecaster, Laura Patterson, said.

During this time, 5 – 10 cm (2 – 4 inches) of snow is expected quite widely. Where showers become organized though, most likely across Scotland and over the hills of northern England, some places are likely to have an additional 15 – 25 cm (6 – 10 inches) of snow, locally as much as 40 cm (16 inches).

Strong winds will lead to drifting of snow and severe wind chill, while lightning could be an additional hazard, particularly near coasts.

The Portuguese met service @ipma_pt named #StormEmma yesterday, set to bring heavy rain and gales across Spain and Portugal. As the storm bumps into the cold air across the UK, there is the risk of blizzards and freezing rain pic.twitter.com/EUgLEkkIXN

Further snow is expected on Thursday and Friday, as Storm Emma pushes into southern England from the continent. This could lead to significantly disruptive snow across the southern UK, while gales and freezing rain could pose additional major hazards in places, increasing the risk of power cuts.

Amber warning for snow and ice is in effect between 14:00 local time, March 1 and 08:00 local time, March 2 for the following regions:

London & South East England

South West England

Wales

West Midlands

Chief Forecaster’s assessment

A weather system is expected to move slowly north through Thursday, intensifying and pushing north across the warning area from Thursday afternoon. As it comes into contact with the very cold air resident over the UK, it has potential to produce widespread snow, accompanied by strong to gale force winds.

As less cold air follows from the south, there is a chance of snow turning to freezing rain bringing an additional significant ice risk. There is still uncertainty in how this system will develop, but there is a chance that the combined effects of snow, strong winds and ice will lead to severe impacts.

Freezing rain is relatively rare in the UK and can be a very hazardous phenomena affecting roads and other infrastructure potentially causing travel disruption. It starts life as snow, ice, or hail, which melts as it passes through a band of warm air as it falls, before refreezing in a band of colder air. The rain droplets become ‘supercooled’ and are close to or below freezing when they hit the ground, freezing on impact.

“This spell of weather is the coldest parts of the country have seen since at least 2013, and there is the potential for disruptive snowfall in many parts throughout the week. Transport disruption is likely in areas with significant snowfall and the cold could have an impact on people’s health,” Patterson said.

“Low temperatures mean snowfall is likely to be powdery, bringing the risk of drifting in the strong easterly winds. The areas affected by snow will vary from day to day and so will the areas at the risk of major impacts. With the weather so severe at the moment it is really important that everyone keeps up to date with the forecast and warnings in their area, check for local travel information and follow the advice of local authorities and emergency services.”